feeling so stuck

i been working at this place for like 5 yrs now and i just feel so stuck man. same cubicle, same projects, same coworkers who always complain about how bad everything is but never do anything to change it. i mean, dont get me wrong, im good at my job and all but its just... i dreamt of doing something bigger than this, you know? like building cool apps or contributing to open source stuff instead of just maintaining some legacy code no one cares about anymore. maybe i should start looking for something else soon but honestly, i dont even know where to begin. it feels like such a big step and im scared of failing. sigh...